CVE-2026-49975 | Apache HTTP Server: mod_http2 denial of service

Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads to denial of service via malicious HTTP requests. This issue affects Apache HTTP Server: from 2.4.17 through 2.4.67.

Published: 2026-06-08 Last update: 2026-06-18 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-49975 is rated Moderate Risk (54.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.31%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-49975

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.51% 1.31% +0.80%
2 2026-06-14 0.42% 0.51% +0.09%
3 2026-06-12 — 0.42% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-49975

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-49975

GitHub Security Advisory for CVE-2026-49975

GHSA-262v-g5h9-6mc6 · Severity: high — Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads...

OS Trackers for CVE-2026-49975

vendor priority summary link
debian not yet assigned CVE-2026-49975 not yet assigned priority: Debian including 1 source packages (apache2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-49975
suse high — https://www.suse.com/security/cve/CVE-2026-49975/
ubuntu medium CVE-2026-49975 medium priority: Ubuntu including 2 source packages (apache2, nginx), 18 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): needs-triage 10, needed 4, released 4. https://ubuntu.com/security/CVE-2026-49975

Affected software / configurations for CVE-2026-49975

Vendor Product Version Raw CPE
apache http_server >= 2.4.17, < 2.4.68 cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
f5 nginx < 1.29.8 cpe:2.3:a:f5:nginx:*:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2026-49975

cvelogic Threat Intelligence